Hydrogen Sulfide Bubble Absorption Enhancement in Water-Based Nanofluids

Abstract

Nanoparticles addition is a novel technique for enhancement of mass transfer in absorption process. A bubble column was used for investigation of hydrogen sulfide (H2S) absorption process. Silica and exfoliated graphene oxide (EGO) were used for preparation of nanofluids used as hydrogen sulfide absorbent. The absorption rate of hydrogen sulfide deteriorated by addition of 14 nm silica nanoparticles to water, while EGO–water nanofluid augmented hydrogen sulfide absorption relative to the base fluid. EGO–water nanofluid with 0.02% wt EGO enhanced absorption rate by 40%. For greater mass percentages of EGO in water, the absorption rate was reduced. It is concluded that EGO–water nanofluid is suitable for H2S absorption. Grazing is the main reason for mass transfer enhancement in EGO–water nanofluids. Mathematical modeling was developed for predicting the effective absorption ratio. The maximum deviation of model predictions from the measurements is 13%.

The influence of silica nanoparticles on hydrodynamics and mass transfer in spray liquid–liquid extraction column

“…In each section, performed studies, type of nanofluids, size and concentration range of nanoparticles, mass transfer measurement method, maximum observed enhancement and suggested mass transport mechanisms were pointed out [13]. In the field of mass transfer in nanofluids, there are a few researches dealt with mass diffusion in nanofluids [1,9,[14][15][16][17][18][19][20] and more researches investigated the influence of nanoparticles on convective mass transfer [10,[21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. Nevertheless, most researches on convective mass transfer in nanofluids are related to the gas absorption processes [21][22][23][24][25][26][27][28][29][30] and there have been limited attempts to use nanofluids in other popular separation processes such as liquid-liquid extraction [10,[34][35][36]…”

The Effect of Various Nanofluids on Absorption Intensification of CO2/SO2 in a Single-Bubble Column

“…For all nanoparticles types, the nanoparticles intensify the micro-convections, producing larger mass transfer rate in comparison to pure basefluid; thus, initial increase in CO 2 absorption would be rationalizable with the aforementioned nanoparticles mass fractions. On the other hands, increasing a number of nanoparticles leads to enhance further the viscosity of nanofluids, thereby overcoming the nanoparticles micro-convection impacts together with diminishing the absorption of CO 2 within the nanofluids [4,12]. Furthermore, Figure 5 clearly exhibits that CO 2 absorption molar flux in metal oxides-based nanofluids is larger than that in deionized water for various nanoparticles mass loads.…”

“…Hence, in 1992, the United Nation Conference on Environment and Development offered a new strategy for reducing the emission of acidic and other greenhouse gases to below the standard level until 2000 [1]. Consequently, the governments should finance researchers and scholars to apply new methods and techniques to reduce the amount of CO 2 as well as the SO 2 produced from large-scale industries and sources [2][3][4][5][6].…”

Experimental investigation of the effects of the hydrophilic silica nanoparticles on mass transfer and hydrodynamics of single drop extraction

“…Nanoparticles finally saturated interface at particle fraction of 0.05%, so for more nanoparticle concentrations, viscosity effects seem to be dominantly responsible for descending trend. Esmaeili Faraj et al's study[34] on absorption of H 2 S into silica nanofluid indicated reduction of absorption rate. They attributed their observation to two main reasons: (1) increasing the viscosity of nanofluid and (2) reduction of the effective fraction of the gas−liquid contact area because of suspended particles presence.…”

“…They attributed their observation to two main reasons: (1) increasing the viscosity of nanofluid and (2) reduction of the effective fraction of the gas−liquid contact area because of suspended particles presence. Esmaeili Faraj et al[34] also investigate the influence of EGO (exfoliated graphene oxide nanoparticles) on absorption rate of H 2 S and observed peak enhancement of 40% using 0.02 wt. % EGO and faced a decreasing trend after this concentration.…”